Die stamping machine



NOV. 7, 1933. H, RANKlN 1,934,277

DIE STAMPING MACHINE Filed Oct. 14, 1932 2 Sheets-Sheet l {NVENTOR 1H IIHIHIIIHHEH'HIH ll ha NOV. 7, 1933. A. H, RANKlN 1,934,277

DIE STAMPING MACHINE" Filed Oct. 14, 1932 2 Sheets-Sheet 2 I INVENTOR f Wis ATT RNEY Patented Nov. 7, 1933 UNITED STATES rsr orrice 13 Claims.

This invention relates to die stamping machines such as are used, for example, for printing, engraving, or embossing sheet material such as paper or cards. An object of the invention is the provision of a simple and compact machine of this character, which may be made inexpensively, which is simple to operate, and by which an inexperienced person can turn out satisfactory work.

Another object of the invention is to provide an improved machine capable of producing exceedingly fine and clean cut impressions in a rapid and efiicient manner.

A further object is the provision of a machine so designed that the movable die will rebound or return automatically after each stamping operation, even though the machine is operated by hand and has no power'return mechanism.

A still further object is the provision of vari- 29 ous improved features and details, such for instance as a non-metallic cutting block on which a die'member may be mounted so that when the die member is cut to trim it down, a knife used in thetrimming operation will come in contact with the non-metallic member and will not be dulled by contact with a metallic member.

To these and other ends the invention resides in certain improvements and combinations of parts, all as will be hereinafter more fully described, the novel features being pointed out in the claims at the end of the specification.

In the drawings: Fig. 1 is a front elevation of a die stamping machine constructed in accordance with a pre "ferred embodiment of the invention; Fig. 2 is a side elevation on a larger scale of the operating parts of the machine, showing the parts in the position of rest;

Fig. 3 is a similar view showing the parts in the stamping position;

Fig. 4 is a horizontal section taken substantially on the line 44 of Fig. 2; and

Fig. 5 is a vertical section taken substantially on the line 5-5 of Fig. 4. j The same reference numerals throughout the several views indicate the same parts.

The die stamping machine herein described as a preferred embodiment of the invention may be used for printing, engraving, or embossing stationery, the term stamping being intended in a broad sense as including printing and engraving operations with ink as well as embossing operations without ink. The machine of the presentv invention operates particularly satisfactorily in printing or engraving operations employing ink, the ink being adequately applied to the stationery without being smeared or smudged, due at least in substantial part to the quick blow delivered by the die and the rapid return movement'of the die.

Referring now to the drawings, there is shown a standard or support 10 of any suitable design carrying a work table 11 and a frame member 12 having a wide shallow groove, as shown in Figs. 1 and 3, for removably receiving a metallic platen member 13 fitting relatively snugly in the groove but capable of sliding longitudinally along the groove. Interlocking means may be provided for preventing such longitudinal sliding movement, such means comprising, for example, the pin 15 (Figs. 3 and 4) extending upwardly fromthe bottom of the groove in the frame member 12 and into a corresponding opening in the under surface of the platen l3.

Mounted on the frame member 12 are suitable paper guides such as the L-shaped members 16 adjustably mounted on the frame member 12 by means. of clamping wing nuts 17. One arm of each of these paper guides 16 overlies the platen 13 directly in contact therewith, in order to hold this platen member down the groovein the frame memberlZ, to prevent accidental upward displacement thereof. The platen may be easily disengaged from the frame member, however, in an instant, by fo'cibly lifting upwardly on the forward projectingend of the platen to disengage the pin 15 from the hole in the platen, and by then pulling forwardly on the platen to slide its rear end out from under the paper guides 16, which paper guides are-somewhat resilient in order to permit such removal and correspond ing replacement of the platen. v

A lateralpaper guide 18 also be provided, having depending pin 18a. for firm engagement withthe supporting frame 12, and being adjustably held by a clamping wing nut 19. Mounted on the platen l3 and preferably set in theplaten so to be flushwith its upper surface, is a non-metallic member 20 of substantial preferably made of fibrous material such as fiber board or the like so that it will not materially injure a knife edge coming into contact with it. On this mounting member 20 is placed a die member 21 of easily severabie material, so that the die member may be trimmed down in area if desired. The area of the nonmetallic mounting member 20 isgreater than the area of the die member 21; thus in any trimming operation performed on the die member, the knife used-to cut through the die member will come in contact with the non-metallic member 20 of fiber or the like, rather than with the metallic platen l3, and the knife blade is not injured or substantially dulled by contact with a metallic surface.

According to the preferred embodiment of the invention, the die member 21 is of resilient material such as rubber composition, so that the cooperating die will rebound from it after a stamping operation, as described hereafter. The rubber composition may be applied to a backing sheet 22 of paper or fabric, which in turn may be cemented to the member 20 by any suitable adhesive indicated diagrammatically by heavy black line 23. After a piece of the rubber composition of convenient area is cemented to the member 20, it may be trimmed down to a size just sufficient to cooperate with the incised or engraved portions of the cooperating die.

Rising from behind the frame member 12 is a column or standard having a generally H shaped cross section as illustrated in Fig. 4, and comprising side walls 25 anda strengthening web 26 between the side walls. At the upper end of this standard 25 are suitable bearings for a shaft 27 carrying at its left hand end a hand wheel 28. Between the two walls 25 of the standard, the shaft 27 has an eccentric 29 fixed to it, which eccentric is embraced by an eccentric strap 30 pivotally connected at 31 to a plunger 32 mounted for substantially vertical movement in a guideway 33 secured to the front of the standard 25. The lower end of the plunger 32 is provided with frontwardly and rearwardly extending flanges 34 which cooperate with slots in a carrier or chase 35 to which the movable die 36 may be secured in any suitable manner as by means of the clamping screws 37. This movable die 36 mounted on the plunger 32 is usually the female die, and is positioned directly over the resilient die member 21 which forms the male die.

The upper edge of the strengthening rib 26 is embraced by suitable material 40 such as a block of rubber which engages the eccentric strap 30 at a certain point in its rearward move- I ment, as shown in Fig. 2, and thus acts as stop means limiting further rotation of the hand wheel 28 and shaft 27 in a clockwise direction when viei ed as in Fig. 2.

She rotating parts of the apparatus are provided with eccentric weight means such as the web 4 formed on the hand wheel 28 as shown in Figs. 2 and 3, which web gives one side of the hand wheel greater weight than the diametrically opposite side, and thus provides eccentric weight. When the hand wheel is moved to the position shown in Fig. 2 where the eccentric strap engages the stop member 40, which may be termed the position of rest of the parts, the web 45 has its center of gravity rearwardly of dead center (that is, rearwardly of the shaft 27) Thus the weight 45 tends to rotate the hand wheel further in a clockwise direction and keeps the parts in engagement with the stop member The throw of the eccentric 29 and the position of the eccentric on the shaft 27 are so designed that a minor part of a revolution of the hand wheel, preferably about a quarter of a revolution, cient to move the die 36 from the position of rest shown in Fig. 2 to the stamping position in contact with the lower die 21 (or in contact with sheet material placed on the lower die). This stampingposition of the parts is illustrated in Fig. 3, and it will be noted that the center of the gravity of the weighted portion 45 of the hand wheel is now slightly forward of dead center; that is, slightly forward of a vertical plane passing axially through the shaft 27. Consequently the effect of this eccentric weight 45, supplemented by the similar effect of the weight of the ccentric 29 itself which also is forwardly of dead center, tends to turn the shaft 27 in a counterclockwise direction when viewed as in and thus assists in delivering the stamping blow of the die 36 upon the sheet material placed on the lower die 21.

1 The weight and proportions of the various mov ng parts, including the eccentricity and po- S1 of the eccc' lo 29, are so chosen that they cons tute wl'iat ht be termed a reversible nanica]. movei...cnt; that is, a mechanical movement in which power may be applied at either end to operate the other end. Not only will force applied to the hand wheel 28 move the die 36, but also upward force applied to the die 36 will cause return movement of the hand wheel. It will be noted from Fig. 3 that when the parts are in the stamping position, the eccentric 29 is approximately midway between its diametrically opposite dead center positions. Consequently the rebounding force transmitted from the member 21 through the, plunger 32 and eccentric strap 30 acts with approximately maximum efficiency in tending to reverse the movement of the rotating parts. This reversible mechanical movement is quite distinct from the mechanical movements heretofore commonly used in die stamping machines. For instance, in some common forms of die stamping machine, where the die is operated by a screw of the pitch customarily employed, rotation of the screw will move the die, but force applied to the die will not be effective to move the screw. The reversible mechanical movement is one of the important features of this invention, as it permits easy and rapid operation, and automatic return of the parts to initial or rest position, as brought out hereafter in the description of the operation.

. In operation, the die to be used in engraving or embossing paper or the like is suitably clamped in the'chase 35, and the chase is placed on the bottom end of the plunger 32 by a horizontal sliding movement engaging the grooves of the chase with the flanges 34 on the plunger.

The platen 13, removed from the machine for more convenient access to it, has a piece of suit able resilient material such as rubber composition 21 cemented to the block 20. The platen is then replaced in the machine by sliding the rear end of it under the paper guides 16, meanwhile holding the front slightly elevated until the rear end of the platen has reached its final position, then dropping the front end down so that the pin 15 engages in the hole in the platen.

The operator now grasps the hand wheel 28 and turns it violently in a forward direction (or counterclockwise direction when viewed as in Figs. 2 and 3) from the position shown in Fig. 2 to the position shown in Fig. 3, which causes the engraved die 36 to move violently down upon the resilient die 21 with a sharp blow. The lower die 21, being of resilient material such as rubber composition, conforms to the surface of the upper die, and portions of it rise up into the engraved recess of the upper die. This initial blow above described is usually of such violence that the lower die is permanently deformed to some extent and the surface of it usually retains, at least to some extent, slight ridges or elevated portions corresponding to the engraved or depressed portions of the upper die 36. In some instances this initial violent blow maybe omitted, if it is not desired to cause permanent deformation of the resilient die member 21.

When the hand wheel '28 is returned to its initial or rest position shown in Fig. 2, elevating the upper die once more, the platen 13 can again be removed from the machine, if desired, by raising the front end of the platen slightly to disengage the pin 15 and then pulling forward ly on the platen, and any unnecessary portions of the lower die 21 can be trimmed away to avoid any possibility of making undesired marks on the paper to be stamped. During such trimming, the trimming knife comes in contact with the non metallic portion 20 of fiber or the like, and thus does not become dulled by contact with the metallic platen 13. The platen isthen replaced on the machine as before, and the apparatus is ready for use in the actual engraving or embossing operation.

If the stationery is to be engraved to produce an inked design, monogram, or initial on the paper, the chase 35 is removed from the machine by sliding it horizontally off of the flanges 34, ink is applied to the surface of the die 36 by a brush or the like, and the die is wiped on the usual wiping pad which may be placed conveniently on the work table 11, which wiping pad removes ink from the flat surface of the die, but not from the incised or engraved portions there-' of. The inked and wiped die is now replaced on the lower end of the plunger 32, a piece of paper is placed on the platen 13 over the lower die in the position as determined by suitable adjustment of the paper guides 16 and 18, and the hand wheel 28 is grasped by the operator and given a quick pull forwardly or in a counterclockwise direction. A momentary quick pull on the hand wheel is sufficient; the operator need not, and in fact should not, retain hold of the hand wheel until the completion of its forward movement.

The momentary forward impetus of the hand wheel is sufiicient to overcome the tendency of the wheel to remain in its rest position, due to the eccentrically weighted portion 45. The rotating mass of the wheel, together with the gravity efiect of the eccentric 29 and of the weighted portion 45 after it passes dead center, is sufii cient to continue motion of the rotating parts enough to bring the upper die down with a'sharp and rapid blow onto the sheet of paper overlying the lower die. This sharp blow transfers the ink from the die to the paper, and compresses the lower resilient die 21, which resilient die immediately pushes upwardly on the upper die and causes the upper die to rebound and move upwardly again. This upward movement is possible because of the reversible nature of the mechanical movement for moving the upper die, as above explained. Consequently, immediately upon making this stamping blow upon I,

the lower die the upper die reboundsupwardly and the hand wheel 28 and associated rotating parts reverse their direction of movement and return clockwise to their initial position of rest illustrated in Fig. 2. .If the rebounding force caused by the resilient lower die would not alone be sufiicient to return the parts quite to their rest position, this is immaterial since in any case, when the machine is properly operated,

the rebounding force moves the wheel far enough so that the center of gravity of the weight 45 is behind dead center, and this weight itself is then effective to complete the return movement of the rotating parts to the rest position, in which the parts are stopped by the stop means 40.

During'the stamping operation, the resilient die 21 not only is compressed as a whole, but also it is usually momentarily deformed so that it pushes the paper up fully into the engraved grooves or depressions of the upper die,v embossing the paper to some extent. With a die properly cut for embossing rather than engraving, the embossing eifect alone can be produced on the paper, if desired, and the inking of the upper die can be omitted.

After the delivery of a stamping blow on the paper and the automatic return of 'the parts as above described, the'stamped sheetof paper is removed from the platen, a fresh sheet of paper is placed on the platen, the upper die is removed, inked, wiped, and replaced on the'plunger 32, and the hand Wheel 28 is once more given 'a momentary quick pull forwardly, which delivers the stamping blow and causes the parts to re-' bound to their initial rest position. The opera tion is then repeated as often as may be desired.

-While'one embodiment of the invention has been disclosed, it is to be understood that the inventive idea may be carried out in a number of ways. This application is therefore not to be limited to the precise details described, but is intended to cover all variations andmodifications thereof falling Within the spirit of the invention orthe scope of the appended claims.

' I claim:

1. A die stamping machine comprising a work position to be impacted by said die to cause said die to rebound from its stamping position toward said rest position.

2. A die stamping machine comprising a resilient platen for holding sheet materiaLa plung- 7 er having a normal position of restand being movable from said position toward said platen, a die removably mounted on said plunger for cooperation with sheet material on said platen when said plunger is moved toward .said platen, and a rotary hand wheel effective upon less than a-single revolution to move said plunger from said position of rest to a position in which said die cooperates with said sheet material, the resilience of said platen causing said plunger and'die to rebound toward said position of rest.

3. A die stamping machine comprising a platen of rubber-like material for holding sheet material, a plunger having a normal position of rest and being movable fromsaid position toward said platen, a die mounted on said plunger for cooperation with sheet material on said platen when said plunger, is moved toward said platen, a shaft mounted for rotation, an eccentric fixed to said shaft, an eccentric strap embracing said eccentric and operatively connected to said plunger, and a hand wheel mounted on said shaft for turning said shaft through less than a single revolution to move said plunger from said position of rest to a position in which said die cooperates with said sheet material, the resilience of said rubber-like platen causing said plunger and die to rebound from said last mentioned position to said position of rest.

4. A die stamping machine comprising means for holding sheet material in position to be stamped, a die movable from a position of rest spaced from said sheet material to a stamping position cooperating with said sheet material, rotary means operatively connected to said die and movable in one direction from a position of rest to shift said die from its position of rest to its stamping position, and resilient means in position to be impacted by said die only when s: "d die substantially reaches said stamping position, for causing said die and rotary means to rebound to their positions of rest.

5. A die stamping machine comprising means for holding sheet material in position to be stamped, a die movable from a position of rest spaced from said sheet material to a stamping position cooperating with said sheet material, means including a flywheel operatively connected tosaid die and eiiective when given an impetus in one direction from a position of rest to said die from its position of rest to its 1g position, and resilient means inefiective o flywheel die until they reach substa. their stamping positions for causing said die and flywheel immediately on reaching their stamping positions to rebound from their stamping positions.

6. A die stamping machine comprising means for holding sheet material in position to be stamped, a die movable from a position of rest spaced from said sheet material to a stamping position cooperating with said sheet material, means including a flywheel operatively connected to said die and eiiective when given an impetus in one direction from a position of rest to shift said die from its position of rest to its stamping position, and resilient means acting by i pact effective only when said die substantially reaches its stamping position for causing both said die andsaid flywheel to rebound to their respective positions of rest immediately when the die reaches its stamping position.

7. A die stamping machine comprising means for holding sheet material in position to be stamped, a die movable from a position of rest spaced from said sheet material to a stamping position cooperating with said sheet material, ro tary means operatively connected to said dieand movable in one direction from aposition of rest to shift said die "from its position of rest. to its stamping position, and a resilient die member for cooperating with die to press sheet material between said die and said die member, the re silience of said die member causing said die when it comes into contact with sheet material on said die member to rebound to its said position of rest. V v

8. A die stamping machine comprising means for holding sheet material in position to be stamped, a die movable from a position of rest spaced from said sheet material to a stamping position cooperating with said sheet material, a flywheel operatively connected to said die and elTective upon movement through a minor part of a single revolution to shift said die from its rest position to its stamping position, said flywheel having a rest position, stop means for determining the rest position of the flywheel, and an eccentric weight on said flywheel tending to impede displacement of said flywheel from its position of rest.

9. A die stampingmachine comprising means for holding sheet material in position to be stamped, a die movable from a position of rest spaced from said sheet material to a stamping position cooperating with said sheet material, a flywheel operatively connected to said die and effective upon movement through a minor part of a single revolution to shift said die from its rest position to its stamping position, said flywheel havng a'rest position, stop means for determining the rest position of the flywheel, an eccentric weight on said flywheel tending to impede displacement of said flywheel from its position or" rest, and resilient means effective only when said die reaches its stamping position to cause said die and flywheel to rebound toward their positions of rest.

10. A die stamping machine comprising means for holding sheet material in position to be stamped, a die movable from a position spaced from said sheet material to a stamping position cooperating with said sheet material, and a hand wheel operatively connected to said die and having eccentric weight means tending, when moved in one direction past dead center, to continue movement of said hand wheel to shift said die from said spaced position to said stamping position.

11. A die stamping machine comprising means for holding sheet material in position to be stamped, a die movable from a position spaced from said sheet material to a stamping position cooperating with said sheet material, operating means mounted for oscillation and operatively connected to said die to move said die from its spaced position to its stamping position, stop means limiting movement of saidoperating means in one direction, and eccentric weight means associated with said operating means and tending when on one side of dead center to hold said operating means against said stop means, and when on the other side of dead center to move said operating means to shift said die to its stamping position.

12. A die stamping machine comprising means for holding sheet material in position to be stamped, a die movable from a position spaced from said sheet material to a stamping position cooperating with said sheet material, reversible mechanical movement means for shifting said die from its spaced position to its stamping position, and resilient means acting by impact and transmitting force to said die only when it reaches its stamping position to restore it from its stamping position to its spaced position, said force acting also to reverse and restore said reversible mechanical movement.

13. A die stamping machine comprising a resilient die member, a die movable from a position spaced from said die member to a stamping position in contact with sheet material placed between said die member and said die, and reversible mechanical movement means for shifti on to its stamp- 

